Printer&#39;s blanket



July 16, 1940. J, 'W, FOSTER 2,207,999

PRINTERS BLANKET Filed Deo. 18, 195'? Patented July 16, 1940 UNITED STATES PATENT OFFICE PRINTERS BLANKET John W. Foster, Ridgewood, N. J., assignor to Tingue Brown & Co., a corporation oi' New York pplication December 18, 1937, Serial No. 180,583

Claims.

5 on the impression cylinder of a printing press,

to make these blankets-identical. In some instances, following the teachings of the Ellis Patent No. 1,855,798, each blanket has been made of Wool or felt and provided with a suitable smooth, flexible coating or face layer, such, for example, as nitro-cellulose or the like, adapted to form the impression surface when at the top. In other instances, following the teachings of the Willson Patent No. 1,545,626, each blanket has l5 been made of comminuted cork carried on a fabric base and provided with an opposite, or upper, face adapted for imprinting directly thereon as described in that patent, these blankets being used ywith a separate top drawsheet overlying the upper lblanket and usually having on a fabric base, a coating or face layer similar to the Ellis face layer mentioned and forming the impression surface. In still other instances, such a drawsheet, or a rubber or felt coated blanket,

or a paper tympan, has been used as a top member, with a pair of transposable corkblankets underneath, these blankets each also having opposite fabric faces, one of muslin or plain weave, and the other of a twill Weave or a drill. However, in all cases, each of the two blankets when used in combination has been identical, not only asto structure, materials, and externalvfaces of each blanket, but also as to gauge and resiliency, lit being believed that this identity constituted a necessary factor in the effective use of such transposable blankets.

My invention has among its objects to provide an improved combination of such transposable blankets wherebyl I am able to obtain improved results, A` further object of my invention is to provide such` an improved combination of itransposable blankets of markedly different resiliency and such as to enable markedly different results to be obtained whenv the blankets are in their differentl transposed positions. A still further object `of 4my invention is to ,provide such an improved combination of4 blankets wherein, irrespective ofwhich blanket is yon top, 'one ofwthe same, 'byjjreasonof its markedly greater resiliencyfis enabled to function in an improved man ner toprevent breaking down ofthe structure of the blankets andrufin ofthe latter by permanent impairment of gauge due to'great pressure should the paper web break. A still further' object of my invention is to provide such an improved combination of blankets wherein, while vcontinuing to provide the above new safety factor, the blankets maybe disposed at will in such manner as to be adapted to use effectively with stereotype plates in widely different condition, my im- 5 proved blankets of widely dierent resiliency being transposable at will in such manner as to adapt the same for use under substantially all plate conditions, i. e. whether the stereotype plates are uniform or irregular. Still another 10 object of my inventionis to provide such an improved combination of blankets wherein, while obtaining the above advantages, it is also made possible to take increased advantage of the favorable characteristics of cork as regards its oil proof 15 character and rapid return to its natural state after compression, while eliminating all need for dii-ferent surfaces or special face layers or other coatings of nitro-cellulose or the like on the blankets, and while also enabling the use of iden- 20 tical and rugged fabric sheets enclosing the cork and forming effective wear resisting opposite faces o f each. blanket. These and other objects of my improved construction will, however, hereinafter more fully appear. l 25 In the accompanying drawing, I have shown for purposes of illustration two embodiments which my invention may assume in practice.

In this drawing- Figure 1 is a perspective View of an impression 30 cylinder equipped with one form of my improvement; the drawsheet and blankets thereon, as well as the printing cylinder, being broken away to facilitate illustration;

Fig. 2 is a at sectional View of the superim- 35 posed blankets and drawsheet in the same arrangement thereof shown in Figure 1, and

Fig. 3 is a view similar to Figure 2, but showing a modified` arrangement. Y I

Referring rst'to the constructionshown in Figures l and 2, it will be noted that I havethere illustrated an impression cylinder I cooperating 'with a plate carrying cylinder 2, the impression cylinder having thereon; my `'improved combination of drawsheet 3 and underlying superimposed 45 blankets 4 and 5,;v these blankets! and ibeing of an improved construction and, Acampera'lt'-ing with the cylindersA Fand ,2L in an improved man'- ner as' hereinafte'lldQSC'lfhed Figlefzlit .Will so Dfbl 'l "'.S frviid with a'l cork filler` 6"co r'riprifsin` rticlesofj ground CPrk treated, with.: oxidizedllinseegufand"united by a suitable'cementQallin the 'well-known' Inainer, this blanket herein also having, on opposite 55 also by the ineness to which the particles of cork therein are ground, as well as by the type of oxidized linseed oil or cement used. The blanket 5, on the contrary, While similar in appearance to the blanket 4,is markedly different in construcf tion and effect. This blanket, while also using identical fabric 8, similar to or the same as the fabric 1, on its opposite faces, and also being provided with a cork ller 9, has markedly different characteristics from the blanket 4. More particularly, the cork filler 9, while of generally similar construction to the filler 6 of the blanket 4-, is so constructed as to be markedly more resilient thanthe ller 6; this variation, for example, being obtained by suitable variation in the fineness of the particles of the cork and the amount of heat applied during baking, as well as by differences in the type of oxidized linseed oil used and in the cement used. For example, assuming both blankets to be of .063 gauge, the blanket 4 preferably has a yield of .015 when tested with a yieldometer, while the blanket 5 has a yield of .022, while with both blankets of a .083 gauge, the blanket 4 has a yield of .019 and the blanket 5 a yield of .028.

In practice, the blankets 4 and 5 are also preferably of different gauge. For example, Where a hard packing is desirable, and a total packing of .146, a blanket 4 having a gauge of `.083 is used with a blanket 5 having a gauge of .063. On the other hand, where the plate condition is poor and a soft striking surface is desired, a blanket 4 having a gauge of .063 is used in combination with a blanket 5 having a gauge of .083. Thus it will be evident that in addition to the difference in resiliency resulting from the dierent construction of the blankets 4 and 5, a further dierence in resiliency is obtained by using blankets of different gauge. Also, it will be evident that the relative hardness desired may be vfurther varied by varying the gauge, while still maintaining the desired difference in resiliency of the blankets and preferably continuing to use blankets of different gauge, as by, where less hard packing is required, increasing the thickness of the blanket 5 and reducing the thickness of the blanket i, or where a harder packing is required, decreasing `the thickness of "the blanket 5 and increasing the thickness of the blanket 4.

With the blankets arranged as shown in Figure 2, i. e. with the hard and rm blanket 4 beneath the drawsheet 3 and on top of the markedly more resilient blanket 5 of lesser gauge, it will be evident that clean, sharp printing will be obtained as a result of the use of this combination. During printing, the more resilient blanket 5 will also obviously function effectively with the more hard and rm upper blanket 4, in such manner as properly to support the latter and enable it to perform its desired function. Further, due to the increased resiliency of the blanket 5, it will be evident that this blanket will act to provide a safety factor whenever the paper web breaks. More particularly, this blanket 5, due to its markedlygreater resiliency, will yield or compress in thickness without impairment of gauge, as the paper 1s wrapped around the cylfaces thereof, identical sheets of suitable fabric inder under great pressure, in such manner as to form a cushion which takes up this abnormal pressure, thereby preserving the gauge of both blankets and preventing the breaking down of the structure of the blankets, i. e. to a point Where they will not return resiliently to their` former gauge, which would otherwise result.

In Figure 3, I have shown a modified arrangement wherein the blankets 4 and 5 shown in Figure 2 are transposed; the more resilient blanket 5 of lesser gauge now being on the top, i. e. above the blanket 4 and directly beneath the drawsheet 3. In this arrangement,v obviously, the blanket 5, due to its increased resiliency, will accept the maximum of 4impression and return rapidly to normal gauge, While the relatively hard and rm blanket 4, underlying blanket 5 and acting as the base or bottom of the assembly, will yield very little, while giving the necessary hardness for good printing. It will also be evident that with the blanket 5 in this position, the same will continue to function as' above described as a safety blanket should a web break.

As a result of my improved construction, it is possible not only to produce clean, sharp printing when the blanket 4 is on top, as in the combination of Figure 2, which is used Where uniform` stereotype plates are available, but also to make it possible to use the combination of Figure 3 when irregular stereotype plates are in use, the

blanket 5 of markedly greater resiliency then to produce perfect plates, many others throughout the country are notlso equipped, and it is accordingly necessary for the blankets to be adapted to function under Widely different conditions. Moreover, it will be noted that, as a result of my improved structure, improved results are obtained under either condition, the combination of Figure 2, for example, being especially effective in bringing out half-tone work and flner type, while the combination of Figure 3 very materially improves the printing obtainable under uneven plate conditions. Further, whatever the arrangement, the more resilient blanket 5 cooperates with the blanket4 4 in the event of web breakage, to take up the resultant unusual strain and pressure and thereby prevent the ruining of the blankets by the permanent impairment of gauge which would otherwise result.

Thus, with my improved combination, it is made possible to pack presses satisfactorily under substantially all mechanical conditions of the press and, while markedly improving the printing obtainable, under all' conditions producing a more safe and lasting construction in the event of web breakage, than heretofore possible. Attention is also directed to the fact that withthis construction, it is immaterial, due to the provision of identical fabric surfaces, which surface of either the top or bottom blanket, is uppermost.

It will also be evident that, -due to the use of suchsired type of impression sheet may also be used with my improved combination. 'I'hese and oth- Obviously, any deer advantages oi' my improved construction will, however, be clearly apparent to those skilled in the art.

While I have herein specifically described two relations in which my invention may be used in practice, it will be understood that these arrangements are shown for purposes of illustration and thatl the illustrative constructions of the individual blankets may be modified and embodied in other forms without departing from the spirit ofthe invention or-the scope of the appended claims. l

What I claim as new and desire to secure by Letters Patent is:

1. A- pair of printers blankets including, in combination, a plurality of separate and directly engaging transposable blankets, each having a cork ller and fabric top and bottom faces thereon, one of said blankets being relatively hard and rm and the other of greater resiliency.

2. A pair of prlnters blankets including, in combination, a plurality of separate and directly engaging transposable blankets, each having a cork ller and fabric top and bottom faces thereon, each blanket having a cork filler of different resiliency, and said blankets having like fabric faces on the opposite faces of one blanket, and like fabric faces on the opposite faces of the other blanket.

3. A packing for the impression cylinder of a printing press including, in combination, ar plurality of separate transposable blankets of different gauge, each having a cork filler and fabric top and bottom faces thereon, leach blanket having a cork filler of different resiliency and top and bottom fabric faces, a fabric face on one blanket non-adhesively engaging a fabric face on another, and an impression sheet non-adhesively engaging the other fabric face of one of said blankets.

4. A pair. of printers blankets including, in combination, a plurality of separate transposable blankets, each having a cork filler and fabric top and bottom faces thereon, said blankets being of different resiliency andseparated by directly engaging fabric faces and. the blanket of lesser resiliency being relatively hard and firm and disposed over the other.

5. A pair of printers blankets including, in combination, a plurality of separate transposable blankets, each having a cork filler and fabric top' JOHN w.-Fos'rER. 

